Method and apparatus for installing/dressing a wiring harness

ABSTRACT

A wiring harness is enshrouded in a tubular length of stretchable material. The shroud holds pigtails, takeouts, connectors, harness hold-downs and the like which otherwise extend from the harness against a trunk of the harness so that it can be inserted through an opening in a firewall or other structural member of a motor vehicle or other product for installation of the harness. Once inserted through the opening, the shroud is removed, preferably by means of a closure device which initially maintains the shroud as a tubular structure but can be removed to open at least a portion of the tubular structure to facilitate shroud removal. To facilitate installation of the shroud onto a wiring harness, the shroud is initially stretched over a tubular applicator to expand the shroud. A wiring harness is then inserted into the tubular applicator and the shroud is peeled off the tubular applicator onto the wiring harness as the harness is passed through and beyond the applicator to apply the tubular shroud to the harness.

This is a division of application Ser. No. 07/474,980 filed Feb. 5,1990, now U.S. Pat. No. 5,064,970.

BACKGROUND OF THE INVENTION

The present invention relates generally to the installation of a wiringharness used for interconnecting electrical equipment and/or circuitsand, more particularly, to a method and apparatus for dressing orenshrouding such a wiring harness for installation of the harnessthrough an opening of a structural member during manufacture of aproduct including the structural member. The present invention isparticularly applicable to the manufacture of motor vehicles andaccordingly will be described with reference to that application.

Wiring harnesses used for motor vehicle electrical circuits are normallypreformed as a central bundle of electrical conductors. Projecting fromthe bundle at varying locations along its length are pigtails, takeouts,connectors, harness hold-downs and the like which may be referred toherein as extensions. The extensions serve to make connections fromelectrical circuits or equipment to or through the electrical conductorsof the wiring harness to associated electrical circuits or equipment orto hold the harness in place in the motor vehicle. Oftentimes, preformedwiring harnesses must be routed through openings in structural members,for example through the firewall of a motor vehicle, to make therequired connections. When a wiring harness is to be passed through anopening, the extensions tend to catch on the opening and interfere withquick and easy installation of the harness.

Prior to this time, extensions from a wiring harness typically have beentaped against the central bundle or trunk of the wiring harness tofacilitate installation. Unfortunately, the application of tape to theindividual extensions is a time consuming operation.

An alternate wiring harness dressing arrangement involves the use oftubular "heat shrink" material. The extensions from the wiring harnessare held against the harness trunk and a length of tubular heat shrinkmaterial is slid over the harness. Heat is then applied to the heatshrink material causing it to shrink or reduce in size and trap theextensions down to substantially the size of the wiring harness trunk.The dressed wiring harness is then inserted through an opening in amotor vehicle firewall or other structural element. Once fully inserted,the shrink wrap material is ripped from the wiring harness to releasethe extensions for the remainder of the installation of the wiringharness.

Unfortunately, the application of heat shrink material to wiringharnesses requires substantial floor space, the application process isdifficult to control, the application requires at least as much labor astaping and the heat shrink material is more expensive than tape.Further, there have been problems in removing the heat shrink material.Perforations have been formed in the heat shrink material to attempt toovercome the removal problem. However, even if perforations areprovided, problems may persist since excessive heat can bond theperforated sections together. Of course, there is also the possibilitythat excesive heat will damage the wiring harnesses.

Accordingly, there is a need for an improved method and apparatus fordressing wiring harnesses for installation through openings in firewallsor other structural elements of motor vehicles and other products.

Preferably the improved wiring harness installation/dressing method andapparatus would utilize inexpensive materials, be readily applied to andremoved from wiring harnesses, and permit recycling or reuse of at leastsome of the apparatus to further reduce the expenses involved in wiringharness installation operations.

SUMMARY OF THE INVENTION

This need is met by the method and apparatus of the present inventionwherein a wiring harness is enshrouded in a tubular length of preferablystretchable material. The shroud holds the pigtails, takeouts,connectors, harness hold-downs and the like which otherwise extend fromthe harness against the trunk of the harness. Thus dressed orenshrouded, the wiring harness can be extended through an opening in afirewall or other structural member of a motor vehicle or other productfor installation of the harness. Once inserted through the opening, theshroud is removed, preferably by means of a closure device whichinitially maintains the shroud as a tubular structure but can be removedto open at least a portion of the tubular structure to facilitate shroudremoval. As noted, the shroud is preferably made of a "stretchablematerial" which is intended to include without limitation stretchablecloth, elasticized cloth, a rubber product, cloth interwoven withelastic thread or other appropriately stretchable or stretchablyreinforced material. To facilitate installation of the shroud onto awiring harness, the shroud is initially stretched over a tubularapplicator to expand the shroud. A wiring harness is then inserted intothe tubular applicator and the shroud is slid off the tubular applicatoronto the wiring harness as the harness is passed through and beyond theapplicator to apply the tubular shroud to the harness. The applicator isthen returned for reuse.

In accordance with one aspect of the present invention, a wiring harnessshroud comprises a tubular section of stretchable material forenshrouding a wiring harness to be inserted through an opening of astructural member during a manufacturing operation for producing aproduct including the structural member. The tubular section ofstretchable material has two ends, at least one of which is open toreceive the wiring harness. Preferably, the tubular section ofstretchable material comprises closure means extending along at least aportion thereof for releasably closing the tubular section ofstretchable material. The closure means are operable after installationof a dressed wiring harness to open the shroud and thereby rapidlyremove it from the harness.

The stretchable material for example may comprise cloth. In thepresently preferred embodiment of the invention, the tubular section ofstretchable material comprises a generally rectangular piece of clothhaving two opposed short sides and two opposed long sides. The longsides of the piece of cloth are joined to one another by the closuremeans which comprises a single thread chain stitch and tab means forsecuring the chain stitch at one end of the tubular means. The tab meansis forcibly removed from the shroud to open the tubular section ofstretchable material by freeing or releasing the chain stitch. Thetubular section of stretchable material may comprise cloth made of atwo-way stretch blend including spandex.

In accordance with another aspect of the present invention, a wiringharness shroud comprises tubular means for enshrouding a wiring harnessto be inserted through an opening of a structural member during amanufacturing operation for producing a product including the structuralmember. The tubular means is closed by closure means extending along atleast a portion thereof for releasably closing the tubular means. Theclosure means is operated after insertion of the shrouded wiring harnessthrough an opening to at least partially open the tubular means andthereby permit rapid removal of the tubular means from the wiringharness.

The tubular means may comprise a generally rectangular piece of clothhaving two opposed short sides and two opposed long sides. The longsides of the piece of cloth are joined to one another by the closuremeans which preferably comprises a single thread chain stitch and tabmeans for securing the chain stitch at one end of the tubular means. Thetab means is forcibly removed from the shroud to open the tubular meansby freeing or releasing the chain stitch. The cloth forming the tubularmeans is preferably stretchable and may comprise a two-way stretch blendincluding spandex.

In accordance with a further aspect of the present invention, a wiringharness shroud assembly for use in enshrouding a wiring harness prior toinsertion through an opening of a structural member during amanufacturing operation for producing a product including the structuralmember comprises tubular shroud means formed of stretchable material forenshrouding a wiring harness. Closure means extend along at least aportion of the tubular shroud means for releasably closing the tubularshroud means. The closure means are opened to rapidly remove the tubularshroud means from the installed harness. The assembly is completed bytubular applicator means which are positioned within the tubular shroudmeans for expanding the tubular shroud means to facilitate applicationof the tubular shroud means to a wiring harness.

In accordance with yet another aspect of the present invention, a methodfor inserting a wiring harness including extensions projectingtherealong through an opening of a structural member during amanufacturing operation for producing a product including the structuralmember comprises the steps of: forming a tubular shroud member of astretchable material; applying the tubular shroud member to the wiringharness to enshroud and thereby contain the extensions within thetubular shroud member; passing the enshrouded wiring harness through anopening; and, removing the tubular shroud member after the wiringharness has been passed through the opening.

The step of applying the tubular shroud member to the wiring harnesscomprises the steps of: positioning a tubular applicator within thetubular shroud member for expanding the tubular shroud member; and,advancing the tubular applicator and the wiring harness relative to oneanother to thereby transfer the tubular shroud member from the tubularapplicator to the wiring harness.

The step of removing the tubular shroud member after the wiring harnesshas been extended through the opening preferably comprises the steps of:extending closure means along at least a portion of the tubular shroudmember for releasably closing the tubular shroud member; and, operatingthe closure means to rapidly open the tubular shroud member. In thepresently preferred embodiment of the invention, the step of extendingclosure means along at least a portion of the tubular shroud membercomprises the steps of: sewing the tubular shroud member with a singlethread chain stitch; and, providing tab means for securing the chainstitch at one end of the tubular shroud member. For this embodiment, thestep of opening the closure means to rapidly remove the tubular shroudmember comprises forcibly removing the tab means to open the tubularshroud member by freeing or releasing the chain stitch.

In accordance with still another aspect of the present invention, amethod for enshrouding a wiring harness within a tubular shroud memberto contain loose extensions projecting along the wiring harness suchthat the wiring harness can be inserted through an opening of astructural member during a manufacturing operation for producing aproduct including the structural member comprises the steps of: forminga tubular shroud member of a stretchable material; positioning a tubularapplicator within the tubular shroud member for expanding the tubularshroud member; and, applying the tubular shroud member to the wiringharness by advancing the tubular applicator over the wiring harness andtransferring the tubular shroud member from the tubular applicator tothe wiring harness.

The step of forming a tubular shroud member of a stretchable materialpreferably comprises the steps of: forming a generally rectangular pieceof stretchable material having two opposed short sides and two opposedlong sides; and, extending closure means along the two opposed longsides to releasably close the tubular shroud member. The step ofextending closure means along the two opposed long sides to releasablyclose the tubular shroud member is preferably performed by the steps of:sewing the two opposed long sides to one another with a single threadchain stitch; and, providing tab means for securing the chain stitch atone end of the tubular shroud member.

Other features and advantages of the invention will be apparent from thefollowing description, the accompanying drawings and the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a wiring harness shroud assembly inaccordance with the present invention showing a shroud partially removedfrom a tubular applicator;

FIG. 2 is a plan view showing application of the shroud of FIG. 1 to awiring harness;

FIG. 3 is a rectangular piece of stretchable cloth from which the shroudof FIG. 1 is preferably made;

FIG. 4 is a perspective view of a tubular applicator forming a part ofthe wiring harness shroud assembly of FIG. 1 and used to apply theshroud as shown in FIG. 2;

FIG. 5 shows a wiring harness shroud assembly ready for application ofthe shroud to a wiring harness; and,

FIG. 6 is a perspective view on an expanded scale of the preferredshroud closure means or single thread chain stitch and tab means forremoving the closure means after a shrouded or dressed wiring harnesshas been installed.

DETAILED DESCRIPTION OF THE INVENTION

While the present invention was conceived and is being utilized in theautomotive industry for the manufacture of motor vehicles, it will beappreciated that it is generally applicable to the installation of awiring harness into any product including a wiring harness which mustextend through an opening in a structural member of the product.Accordingly, the invention is directed to a method and apparatus fordressing or enshrouding a wiring harness to restrain pigtails, takeouts,connectors, harness hold-downs and the like, which may be referred toherein as extensions, for installation of the wiring harness.

Reference will now be made to the drawing figures wherein a wiringharness shroud assembly 100 in accordance with the present invention isshown in perspective in FIGS. 1 and 5. In FIG. 5, tubular shroud meanscomprising a shroud 102 formed of stretchable material is fully expandedand supported upon tubular applicator means while the shroud 102 isshown as being partially removed from the applicator means in FIG. 1.The tubular applicator means preferably comprises an applicator tube 104of a first diameter which is sized to receive and stretch or expand theshroud 102 for application to a wiring harness 106. A collar 108surrounds and is secured to the application end 104A of the tube 104,i.e. the end of the applicator tube 104 which is moved along the wiringharness 106 to peel the shroud 102 from the tube 104 and apply it to theharness 106.

The wiring harness 106, which can be used for electrical circuits of amotor vehicle or for other applications, is preformed as a central trunkor bundle 106A of electrical conductors. Projecting from the bundle 106Aat varying locations along its length are pigtails 106B, takeouts 106C,connectors 106D, harness hold-downs 106E and the like which arecollectively referred to herein as extensions. The extensions serve tomake connections from electrical circuits or equipment to or through theelectrical conductors of the wiring harness 106 to associated electricalcircuits or equipment or to hold the harness 106 in place. In theillustrated embodiment, the wiring harness 106 is terminated by agrommet 106F which serves to seal the opening through which the harness106 is inserted.

The tube 104 and collar 108 are preferably formed of a stiff cardboardmaterial for a low cost structure yet one which can be repeatedly usedfor a substantial number of shroud applications; however, a variety ofmaterials can be used. For example, the tube 104 and collar 108 can beconstructed of plastic, fiber glass, or other appropriate material. Thecollar 108 serves as a convenient hand-hold for application of theshroud 102 and also defines the limits of the applicator tube 104 forinitial installation of the shroud 102 to the tube 104 prior toapplication of the shroud 102 to the wiring harness 106. The shroud 102is preferably formed of a stretchable material such as a two-way stretchblend cloth including spandex, a rubber or rubberized material, materialreinforced by elastic thread or the like. However, for someapplications, stretchable material may not be utilized.

As shown in FIG. 3, an elongated generally rectangular piece of cloth110 having two opposed short sides 112, 114 and two opposed long sides116, 118 is used to form the shroud 102. The long sides 116, 118 of thepiece of cloth 110 are joined to one another by closure means to definethe tubular shroud 102. The closure means preferably comprises a singlethread chain stitch 120 best shown in FIGS. 1 and 6, and tab means forsecuring the chain stitch 120 at one end of the shroud 102. Whileremovable closure means is shown as extending substantially the entirelength of the shroud 102 in the illustrated embodiments, in someapplications the shroud 102 may include removable closure means onlyalong a portion of its length. The tab means is forcibly removed to openthe shroud 102 by freeing or releasing the chain stitch 120. Typically,the chain stitch 120 will then unravel.

In the presently preferred embodiment, the tab means comprises apolymeric shaft 122 having an integral tab 124 at one end and anintegral terminating bar 126 at the other end. A removal tag 128includes an aperture 130 through which the shaft 122 extends. The tag128 can be formed of cardboard, polymeric, or other appropriate materialas preferred for a given application. The tab means as illustrated isessentially the same as the ubiquitous price tags which are insertedthrough material of clothing or other items constructed of easilypenetrable material such as cloth. For this application, the shaft 122of the tab means is inserted through one of the last stitches 120A ofthe single thread chain stitch 120 where it helps to perform the closureoperation for the shroud 102 by stabilizing the chain stitch 120 andpreventing its unraveling.

Thus, the tab means serves to hold the chain stitch 120 together duringinstallation of the shroud 102 to the applicator tube 104, applicationof the shroud 102 to the wiring harness 106 and installation of thewiring harness 106 through an opening (not shown) in a structural memberof a product being manufactured. Once the wiring harness 106 has beendressed or enshrouded and installed, the shroud 102 is opened bygrasping the tag 128 and forcibly removing it to open the shroud 102 byreleasing the chain stitch 120. The opened shroud 102 is then removedand may be discarded or retained for reuse as desired.

While the chain stitch 120 is presently preferred for the shroud 102 ofthe invention, it should be appreciated that other closure means arecontemplated. For example, a hook and loop material sold under the nameVelcro which is a registered trademark of Velcro USA Inc. could be used,a polymeric tongue and groove fastener such as used on food storage bagsand the like could be used and other closure structures will besuggested to those skilled in the art. For some applications of thepresent invention, it is contemplated that closure means may not berequired at all. For example, in some applications it is contemplatedthat wiring harnesses to be enshrouded or dressed would includeextensions which would not catch on a permanently closed shroud.

The present invention also encompasses a method for inserting the wiringharness 106 including loose connectors, pigtails and other extensions(106B-106E) therealong through an opening of a structural member duringa manufacturing operation for producing a product including thestructural member. The method of the present invention comprises thesteps of: enshrouding the wiring harness 106 within the tubular shroud102 to contain the connectors, pigtails and other extensions (106B-106E)within the tubular shroud 102; passing the enshrouded wiring harness 106through an opening; and, removing the tubular shroud 102 after thewiring harness 106 has been passed through the opening.

A method of enshrouding the wiring harness 106 within the tubular shroud102 preferably comprises the steps of: forming the tubular shroud 102 ofa stretchable material; positioning the tubular applicator 104 withinthe tubular shroud 102 for expanding the tubular shroud 102; and,applying the tubular shroud 102 to the wiring harness 106 by advancingthe tubular applicator 104 over the wiring harness 106 and transferringthe tubular shroud 102 from the tubular applicator 104 to the wiringharness 106. These steps of the method of the present invention are bestillustrated in FIG. 2 wherein the shroud 102 is being applied to thewiring harness 106 by moving the applicator tube 104 to the right asshown by the arrow 132 relative to the wiring harness 106 while theshroud 102 is slid off the applicator tube 104 onto the wiring harness106. Of course, the shroud 102 can be applied by moving the applicatortube 104 and the wiring harness 106 relative to one another.Accordingly, the shroud 102 can be applied by pulling the wiring harnessthrough the applicator tube 104 or by mutual movement of the two.

The step of removing the tubular shroud 102 after the wiring harness 106has been extended through an opening comprises the steps of: extendingclosure means along at least a portion of the tubular shroud 102 forreleasably closing the tubular shroud 102; and, operating the closuremeans to rapidly open the tubular shroud 102. The step of extendingclosure means along at least a portion of the tubular shroud 102preferably comprises the steps of: sewing the tubular shroud 102 withthe single thread chain stitch 120; and, providing tab means forsecuring the chain stitch 120 at one end of the tubular shroud 102. Thestep of operating the closure means to rapidly open the tubular shroud102 then comprises forcibly removing the tab means to open the tubularshroud 102 by freeing the chain stitch 120.

Having thus described the method and apparatus for dressing a wiringharness of the present invention in detail and by reference to preferredembodiments thereof, it will be apparent that modifications andvariations are possible without departing from the scope of theinvention defined in the appended claims.

What is claimed is:
 1. A method for inserting a wiring harness includingloose extensions projecting therealong through an opening of astructural member during a manufacturing operation for producing aproduct including the structural member comprising the steps of:forminga tubular shroud member of a stretchable material; applying said tubularshroud member to the wiring harness to enshroud and thereby contain theextensions within said tubular shroud member; passing the enshroudedwiring harness through said opening; and removing the tubular shroudmember after the wiring harness has been passed through said opening. 2.A method for inserting a wiring harness including loose extensionsprojecting therealong through an opening of a structural member asclaimed in claim 1 wherein the step of applying said tubular shroudmember to the wiring harness comprises the steps of:positioning atubular applicator within said tubular shroud member for expanding saidtubular shroud member; and advancing said tubular applicator and thewiring harness relative to one another to thereby transfer said tubularshroud member from said tubular applicator to the wiring harness.
 3. Amethod for inserting a wiring harness including loose extensionsprojecting therealong through an opening of a structural member asclaimed in claim 2 wherein said stretchable material comprises cloth. 4.A method for inserting a wiring harness including loose extensionsprojecting therealong through an opening of a structural member asclaimed in claim 3 wherein said stretchable cloth material comprises atwo-way stretch blend including spandex.
 5. A method for inserting awiring harness including loose extensions projecting therealong throughan opening of a structural member as claimed in claim 1 wherein the stepof removing the tubular shroud member after the wiring harness has beenpassed through the opening comprises the steps of:extending closuremeans along at least a portion of a length of said tubular shroud memberfor releasably closing said length of said tubular shroud member; andoperating said closure means to rapidly open said length of said tubularshroud member.
 6. A method for inserting a wiring harness includingloose extensions projecting therealong through an opening of astructural member as claimed in claim 5 wherein the step of extendingclosure means along at least a portion of a length of said tubularshroud member comprises the steps of:sewing said at least a portion ofsaid length of said tubular shroud member with a single thread chainstitch; and providing tab means for securing said chain stitch at oneend of said tubular shroud member.
 7. A method for inserting a wiringharness including loose extensions projecting therealong through anopening of a structural member as claimed in claim 6 wherein the step ofoperating said closure means to rapidly open said tubular shroud membercomprises forcibly removing said tab means to open said tubular shroudmember by releasing said chain stitch.
 8. A method for enshrouding awiring harness within a tubular shroud member to contain looseextensions projecting along said wiring harness such that said wiringharness can be inserted through an opening of a structural member duringa manufacturing operation for producing a product including thestructural member, said method comprising the steps of:forming a tubularshroud member of a stretchable material: positioning a tubularapplicator within said tubular shroud member for expanding said tubularshroud member; and applying said tubular shroud member to the wiringharness by advancing said tubular applicator over the wiring harness andtransferring said tubular shroud member from said tubular applicator tothe wiring harness.
 9. A method for enshrouding a wiring harness withina tubular shroud member as claimed in claim 8 wherein the step offorming a tubular shroud member of a stretchable material comprises thesteps of:forming a generally rectangular piece of stretchable materialhaving two opposed short sides and two opposed long sides; and extendingclosure means along said two opposed long sides to releasably close saidtubular shroud member.
 10. A method for enshrouding a wiring harnesswithin a tubular shroud member as claimed in claim 9 wherein the step ofextending closure means along said two opposed long sides to releasablyclose said tubular shroud member comprises the steps of:sewing said twoopposed long sides to one another with a single thread chain stitch; andproviding tab means for securing said chain stitch at one end of saidtubular shroud member.